Antitumor effects of polyphenol-rich extract of Euphoria longana seed by vascular endothelial growth factor and transforming growth factor-beta signaling inhibition in experimentally induced oral cancer in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Oral cancers are found to have high risk in South Central Asia due to exposure of various risk factors. Euphoria longana Lam. (EL) has been traditionally used to relieve insomnia, prevent amnesia, and treat palpitation. In addition, EL has been reported to have anti-inflammatory, anti-cancer, and antioxidant activities. The investigation was aimed to evaluate the mechanism of action and antitumor activity of polyphenol-rich EL seeds extract against oral cancer induced by 4-Nitroquinoline-1-oxide (4-NQO). MATERIALS AND METHODS: Seven groups of Sprague-Dawley rats were formulated: normal animals, oral cancer induced with 4-NQO, EL-treated normal control, EL-treated disease control from 0-day, EL-treated disease control from 60 days, 5-fluorouracil (5-FU)-treated disease control from day 60, and combined EL- and 5-FU-treated disease control animals from day 60. The animal tongue was smeared with 0.5% 4-NQO at frequency of thrice a week for 12 weeks to induce oral cancer. At the end of treatment, excised tongues were used for biochemical and tumour-specific parameters along with histopathology assessment. RESULTS: Treatment with EL, 5-FU, and combination of both in diseased animals exhibited significant improvement in interleukin-6, vascular endothelial growth factor (VEGF), and Transforming growth factor beta (TGF-ß) levels, antioxidant status together with histoarchitecture of the tongue tissue. In addition, the combination of both was slightly more effective than EL and 5-FU alone. CONCLUSION: Our data suggest antitumor activity of Euphoria longana Lam. Extract against 4-NQO induced oral cancer in rats, which could be attributed to alteration in the VEGF and TGF-ß signaling axis.

Evaluation of the Chemopreventive Activity of Grape Skin Extract Using Medium-term Oral Carcinogenesis Assay Induced by 4-Nitroquinoline 1-Oxide.

BACKGROUND/AIM: The aim of this study was to evaluate the chemoprotective potential of grape skin extract following rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide (4NQO). MATERIALS AND METHODS: Male Wistar rats were distributed into four groups (n=5, per group): Control Group: free access to commercial diet and drinking water for 12 weeks; 4NQO Group: received 4NQO diluted in drinking water daily, for 12 weeks; Grape Skin Extract Group: free access to water and received grape skin extract incorporated with diet for 12 weeks; 4NQO + Grape Skin Extract Group: received 4NQO in drinking water daily and grape extract incorporated with diet for 12 weeks. RESULTS: Animals treated with grape skin extract revealed a significant reduction in epithelial dysplasia. Also, 8-hydroxy-2'-deoxyguanosine (8-OHdG) and ki-67 immunoexpression was reduced in animals treated with grape skin extract. Western blot analysis showed a significant decrease of p-NFκB p50 and MyD88 protein expression in the groups treated with grape skin extract. Copper-zinc superoxide dismutase, manganese superoxide dismutase, and catalase gene expression did not present any statistically significant differences (p>0.05). CONCLUSION: Grape skin extract displayed chemopreventive activity in oral carcinogenesis assays as depicted by its antioxidant, anti-proliferative and anti-inflammatory properties.

Prevention of oral carcinogenesis in rats by Dracaena cinnabari resin extracts.

OBJECTIVES: In vivo study was performed to determine the chemopreventive efficacy of the DC resin methanol extract on a 4-nitroquinoline-1-oxide (4NQO) oral cancer animal model. MATERIALS AND METHODS: This study involves administration of 4NQO solution for 8 weeks alone (cancer induction) or with Dracaena cinnabari (DC) extract at 100, 500, and 1000 mg/kg. DC extract administration started 1 week before exposure until 1 week after the carcinogen exposure was stopped. All rats were sacrificed after 22 weeks, and histological analysis was performed to assess any incidence of pathological changes. Immunohistochemical expressions of selected tumor marker antibodies were analyzed using an image analyzer computer system, and the expression of selected genes involved in apoptosis and proliferative mechanism related to oral cancer were evaluated using RT2-PCR. RESULTS: The incidence of OSCC decreased with the administration of DC extract at 100, 500, and 1000 mg/kg compared to the induced cancer group. The developed tumor was also observed to be smaller when compared to the induced cancer group. The DC 1000 mg/kg group inhibits the expression of Cyclin D1, Ki-67, Bcl-2, and p53 proteins. It was observed that DC 1000 mg/kg induced apoptosis by upregulation of Bax and Casp3 genes and downregulation of Tp53, Bcl-2, Cox-2, Cyclin D1, and EGFR genes when compared to the induced cancer group. CONCLUSIONS: The data indicated that systemic administration of the DC resin methanol extract has anticarcinogenic potency on oral carcinogenesis. CLINICAL RELEVANCE: Chemoprevention with DC resin methanol extract may significantly reduce morbidity and possibly mortality from OSCC.

Protective effects of purple carrot extract (Daucus carota) against rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide.

The aim of this study was to evaluate the chemopreventive potential of purple carrot extract following rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide (4NQO). For this purpose, histopathological analysis, proliferative status, antioxidant activity and inflammatory status were investigated in this setting. A total of 20 male rats were distributed into four groups as follows (n = 5 per group): Group 1-free access to water and commercial diet for 12 weeks; Group 2-received 4NQO at 50 ppm dose in drinking water daily and commercial diet for 12 weeks; Group 3-free access to water and received diet supplemented with purple carrot extract (0.1 g/kg) for 12 weeks; and Group 4-received 4NQO at 50 ppm dose in drinking water daily and diet supplemented with purple carrot extract (0.1 g/kg) for 12 weeks. Histopathological analysis revealed that animals treated with purple carrot extract reduced the oral lesions such as dysplasia and squamous cell carcinoma. Animals with oral pre-neoplastic lesions and treated with purple carrot extract decreased ki-67 and 8-OHdG immunoexpression. Moreover, pNFκBp50 and MyD88 protein expressions were decreased after purple carrot treatment associated or not with 4NQO exposure. SOD-Mn mRNA levels increased with treatment with purple carrot extract as well. In conclusion, our results demonstrated that purple carrot extract was able to protect oral lesions induced by 4NQO in Wistar rats as a result of antioxidant activity, anti-inflammatory potential and antiproliferative and antimutagenic actions.

Antioxidant, Antigenotoxic and Cytotoxic Activity of Anthocephalus cadamba (Roxb.) Miq. Bark Fractions and their Phytochemical Analysis using UPLC-ESI-QTOF-MS.

BACKGROUND: Anthocephalus cadamba is used in traditional and folklore medicinal system. OBJECTIVES: In order to validate its traditional medicinal claim, the present study was designed to assess antioxidant, antigenotoxic and cytotoxic activity of fractions from Anthocephalus cadamba bark and to identify their active phytoconstituents. METHODS: The four fractions viz. hexane (HACB), chloroform (CACB), ethylacetate (EACB) and nbutanol (NACB) were fractionated from the crude methanol extract from bark of A. cadamba. All fractions were evaluated for antiradical efficacy using various in vitro antioxidant assays and for antigenotoxicity by SOS chromotest using E. coli PQ37 tester strain. Cytotoxic potential was checked using MTT assay. RESULTS: Among the four fractions, EACB and NACB exhibited promising radical quenching potential in DPPH, ABTS, superoxide anion radical scavenging and pBR322 plasmid DNA nicking assays. All the fractions were evaluated for genotoxic and antigenotoxic activity in SOS chromotest using E. coli PQ37 tester strain. Results revealed that fractions were non-genotoxic and have potential to suppress the genotoxicity induced by 4NQO (4-nitroquinoline-1-oxide) and AFB1 (aflatoxin B1). NACB was found to inhibit the growth of colon (COLO 205) cancer cells with GI50 of 54.36 µg/ml. To identify bioactive principles in the active fractions, NACB and EACB were subjected to UPLC-electrospray-ionization-quadrupole time-of-flight mass spectrometry which revealed the presence of 3ß-isodihyrocadambine-oxide, cadambine, phelasin A/B, 3ß- dihydrocadambine and 3'-O-caffeoylsweroside like compounds. CONCLUSIONS: Overall results revealed that A. cadamba is a rich source of antioxidant, antigenotoxic and cytotoxic constituents which may find their significance in various food and pharmaceutical products.

Geraniol attenuates 4NQO-induced tongue carcinogenesis through downregulating the activation of NF-κB in rats.

Geraniol, an acyclic monoterpene found in lemon grass and aromatic herb oil, has been shown to exert antitumor and antioxidant activities against various cancer types. The objective of this study was to investigate the potential chemoprotective role of geraniol against 4-nitroquinoline-1-oxide (4NQO)-induced oral carcinogenesis in male Wistar rats and furthermore to study anti-inflammatory mechanisms of action through possible NF-κB signaling. 4NQO was administered to rats at the dose of 50 ppm through drinking water to induce tongue cancer in 20 weeks. 4NQO provoked inflammation by upregulating the expressions of the p65 subunit nuclear factor kappa-ß (NF-κB) in the nucleus, tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS). Additionally, staining for immature and mature mast cells in cancer niche by toluidine blue staining and alcian blue-safranin staining showed more accumulation. Co-treatment of geraniol 200 mg/kg b.w. showed a significant decrease in the level of p65 NF-κB in the nucleus, and this might be due to the inhibition of NF-κB activation/translocation into nucleus, which was further confirmed by decreased immature and mature mast cell density and the expression of inflammatory downstream mediators such as TNF-α, IL-1ß, COX-2, and iNOS. Collectively, our results suggested that geraniol as a potential anti-inflammatory agent having the capability to obstruct 4NQO initiated NF-κB activation and modulated the expression of inflammatory mediators.

Alleviation of 4-nitroquinoline 1-oxide induced oxidative stress by Oroxylum indicum (L.) leaf extract in albino Wistar rats.

BACKGROUND: 4-nitroquinoline 1-oxide (4-NQO) is a mutagen known to be responsible for causing cancer by generating oxidative stress in humans. Oroxylum indicum (L.) possesses various bioactive compounds with antioxidant properties. In this connection, the present study aims to analyze the alleviation of 4-NQO induced oxidative stress in albino Wistar rats using O. indicum (L.) leaf extract. METHODS: O. indicum (L.) belonging to the family Bignoniaceae, has anticancer and anti-inflammatory properties. In this study, we observed severe oxidative stress in 4-NQO induced albino Wistar rats when compared to untreated control. Alleviation of this condition was seen after the oral administration of O. indicum (L.) leaf extract at 50, 100, and 200 mg/kg body weight. RESULTS: 4-NQO (50 ppm) administration in drinking water resulted in the generation of reactive oxygen species (ROS) leading to cellular damage, lipid peroxidation and imbalance in antioxidant status. Administration of O. indicum (L.) leaf extract has alleviated the level of 4-NQO induced oxidative stress by increasing the antioxidant status and decreasing the elevation of liver markers in serum. CONCLUSIONS: Results clearly suggest that O. indicum (L.) leaf extract when administered orally in a dose dependent manner has the ability to overcome the oxidative stress induced by 4-NQO with hepatoprotective and lipid protective properties.

Antioxidant activity of apple extract protects against rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide.

Several studies have shown that apple (Malus sp.) has many components able to exert chemopreventive activity. The aim of this study was to evaluate the chemopreventive potential of apple extract following medium-term oral carcinogenesis assay induced by 4-nitroquinoline 1-oxide (4NQO) by means of histopathological analysis and gene expression of antioxidant enzymes, such as CuZnSOD, MnSOD and catalase. A total of 30 male Wistar rats were distributed into five groups, as follows (n = 6 per group): Group 1 - negative control group (non-treated group); Group 2 - received 4NQO during 8 weeks in drinking water and treated with apple extract by gavage between the 1st and 4th weeks daily (initiation phase); Group 3 - received 4NQO for 8 weeks in drinking water and treated with apple extract by gavage between the 5th and 8th weeks daily (promotion phase); Group 4 - received apple extract by gavage for eight consecutive weeks only; and Group 5 - received 4NQO for 8 weeks in drinking water daily. Histopathological analysis revealed that apple extract protect oral lesions induced by 4NQO at initiation or promotion phase. Higher gene expression of CuZnSOD and MnSOD enzymes were noticed in groups treated with apple extract as well. Taken together, our results demonstrate that the apple extract is able to modulate medium-term oral carcinogenesis assay as a result of antioxidant activity.

Chemopreventive activity of systemically administered curcumin on oral cancer in the 4-nitroquinoline 1-oxide model.

Curcumin has therapeutic potential in preventing several types of cancer, including colon, liver, prostate, and breast. The goal of this study was to evaluate the chemopreventive activity of systemically administered curcumin on oral carcinogenesis induced by 4-nitroquinolone-1-oxide (4-NQO). A total of 50 male albino rats, Rattus norvegicus, (Holtzman), were divided into five groups (n = 10 per group). Four of these groups were exposed to 50 ppm 4-NQO in their drinking water ad libitum for 8 or 12 weeks, two groups were treated with curcumin by oral gavage at 30 or 100 mg/kg per day, and one group was treated with corn oil (vehicle) only. The negative control group was euthanized at baseline. Tongues of all animals were removed after euthanasia and used in the subsequent analysis because the tongue is the primary site of carcinogenesis in this model. Descriptive histological analysis and immunohistochemistry for PCNA, Bcl-2, SOCS1 e-3, and STAT3 were performed to assess the oncogenic process. The gene expression of Vimentin, E-cadherin, N-cadherin, or TWIST1 was assessed using RT-qPCR as a representative of epithelial-mesenchymal transition (EMT) events. The administration of curcumin at 100 mg/kg during the 12 weeks markedly decreased the expression of PCNA, Bcl-2, SOCS1 e -3, and STAT3. Curcumin also minimized the cellular atypia under microscopic analysis and diminished the expression of the genes associated with EMT. These findings demonstrate that the systemic administration of curcumin has chemopreventive activity during oral carcinogenesis induced by 4-NQO.

Assessment of 5-fluorouracil and 4-nitroquinoline-1-oxide in vivo genotoxicity with Pig-a mutation and micronucleus endpoints.

Genotoxicity assessments were conducted on male Sprague Dawley rats treated with 5-fluorouracil (5-FU) and 4-nitroquinoline-1-oxide (4NQO) as part of an international validation trial of the Pig-a mutant phenotype assay. Rats were orally exposed to 0, 11.5, 23, or 46 mg/kg/day 5-FU for three consecutive days (Days 1-3); blood was sampled on Days -1, 4, 15, 29, and 45. Pig-a mutant phenotype reticulocyte (RET(CD59-)) and mutant phenotype erythrocyte (RBC(CD59-)) frequencies were determined on Days -1, 15, 29, and 45, and percent micronucleated reticulocytes (%MN-RET) were measured on Day 4. Rats were treated with 4NQO for 28 consecutive days by oral gavage, at doses of 1.5, 3, or 6 mg/kg/day. RBC(CD59-) and RET(CD59-) frequencies were determined on Days -1, 15, and 29, and MN-RET were quantified on Day 29. Whereas 5-FU was found to increase %MN-RET, no significant increases were observed for RBC(CD59-) or RET(CD59-) at any of the time points studied. The high dose of 4NQO (6 mg/kg/day) was observed to markedly increase RBC(CD59-) and RET(CD59-) frequencies, and this same dose level caused a weak but significantly elevated increase in MN-RET (approximately twofold). Collectively, the results provide additional support for the combination of Pig-a mutation and MN-RET into acute and 28-day repeat-dose studies.

Chemopreventive activity of apple extract following medium-term oral carcinogenesis assay induced by 4-nitroquinoline-1-oxide.

OBJECTIVE: The aim of this study was to evaluate the chemopreventive activity of an apple extract following medium-term oral carcinogenesis assay induced by 4-nitroquinoline-1-oxide (4NQO). METHODS: A total of 30 male Wistar rats were distributed into five groups as follows (n=6 per group): Group 1, negative control group (non-treated group); Group 2, received 4NQO during 8 weeks in drinking water and treated with apple extract at 1% by gavage between the first and fourth weeks daily (initiation phase); Group 3, received 4NQO for 8 weeks in drinking water and treated with apple extract by gavage at 1% between the fifth and eighth weeks daily (promotion phase); Group 4, received apple extract at 1% by gavage for 8 consecutive weeks only; and Group 5, received 4NQO for 8 weeks in drinking water daily. RESULTS: Histopathological analysis revealed decreased hyperplasic lesions in Group 2 when compared with Group 5. Likewise, decreased dysplastic lesions in Group 3 were observed when compared with Group 5. In Groups 2 and 3, decreased COX-2 and TNF-alpha gene expressions were observed when compared with Group 5. Cytochrome c and caspase 3 levels increased in Groups 2 and 3 when compared with Group 5. CONCLUSION: In conclusion, our results demonstrate that apple extract suppresses rat tongue carcinogenesis as a result of anti-inflammatory activity and apoptosis through the intrinsic mitochondrial pathway.

Metabolite profiling of polyphenols in Vaccinium berries and determination of their chemopreventive properties.

A detailed investigation on the chemical composition and chemopreventive activity of Vaccinium floribundum Kunth berries was carried out in comparison with Vaccinium myrtillus L. Berry polyphenols were extracted by using two sequential dynamic maceration steps, which enabled to maximize the yields of secondary metabolites. In particular, phenolic acids and flavonols were extracted from berries using ethyl acetate (EtOAc), whereas anthocyanins were extracted from the residue with 0.6M HCl in methanol (MeOH). The analysis of secondary metabolites in berry extracts was performed by means of two specific HPLC methods. Phenolic acids and flavonols were analyzed on an Ascentis C18 column (250mm×4.6mm I.D., 5µm), with a gradient mobile phase composed of 0.1M HCOOH in H2O and ACN. Anthocyanin analysis was carried out on a Zorbax SB-C18 column (150mm×4.6mm I.D., 5µm), with a gradient mobile phase composed of H2O-HCOOH (9:1, v/v) and MeOH-H2O-HCOOH (5:4:1, v/v/v). Detection was performed by UV/DAD, MS and MS(2). The polyphenol composition of V. floribundum and V. myrtillus was studied in detail. The samples of V. floribundum analyzed in this study had a much higher content of both phenolic acids and flavonols in comparison with V. myrtillus (mean value 41.6±10.2 and 13.7±0.2mg/100g FW, respectively), while V. myrtillus showed a higher amount of anthocyanins if compared with V. floribundum (568.8±8.8 and mean value 376.2±49.9mg/100gFW, respectively). The extracts gave negative results in antimutagenic assays against carcinogens 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ) and 4-nitroquinoline-1-oxide (4-NQO), while they performed similarly in both ABTS(+) and DPPH antioxidant assays.

Inhibitory Effect of Chinese Herbal Compound Dongju on Tongue Carcinogenesis in Rats / 上海第二医科大学学报

Objective To examine the inhibitory effect of Chinese herbal Compound Dongju on 4-nitroquinoline 1-oxide(4NQO)-induced tongue carcinogenesis in rats. Methods A total of 85 Wistar rats were divided into four groups: model group(n=35),administration group(n=35),normal control group(n=5) and herb control group(n=10).4NQO dissolved in drinking water was administered orally to induce tongue carcinogenesis in rats.The herb compound was injected into the stomach of the rats during oral carcinogenesis.Rats were sacrificed at 9,13,20,24 and 32 weeks from the beginning of the experiment.The tongues of the rats were dissected for gross and histological assessment,and SP immunohistochemical method was also employed to detect the expression of cyclin D1 in the specimens. Results Compared with the model group,the incidence of dysplasia and the positive rate of cyclin D1 were suppressed by Compound Dongju(P